We ate at both breakfasts on our trip in December and much prefered the food and atmosphere at Crystal Palace over Chef Mickeys. If you want to see Pooh and his friends it's great. My advice for getting done before rope drop: get your check settled as early as possible, especially if you are on a dining plan. It took atleast 10-15 minutes for our waiter to bring the original check, take our dining card and apply it, take our credit card to apply towards the tip and get everything signed and out the door. It took atleast 3-4 trips to get it taken care of, and of course, we weren't his only table. We had 8:15am ADR's but were seated right at opening because we checked in right away. We finished and were out of the restaurant by 9:10am and on Dumbo a little later with only a 10 minute wait. Not too bad considering we missed rope drop, but eating at CP, you're already half way there to most of the rides in Fantasy/Adventure/or Frontier Land.
You also can't beat being in Magic Kingdom before the crowds get there. The pictures of Cinderella's Castle with nobody standing in front of it is wonderful. It's also quite peaceful walking to the restaurant with so few people around.
One more bit of info. You cannot get through the gates at Magic Kingdom until 7:45am (others day 7:50am, but my DH's watch read 7:45am). You can get through security and wait in the breakfast waiting lines at the gates on the far right hand side of the park entrance. But, no matter how early you get there (we arrived around 7:20am), you won't be let into the park until 7:45am. The lines were kind of long, but not bad. We were about the 6th or 7th family in our line so it only took a few minutes of waiting once the gates had been opened. Also, buses begin running to Magic Kingdom around 6:30am (some claim earlier) but they don't come as frequently as the normal schedule buses.
Hope this info helps. Enjoy your trip!